Flashcards in Spring 9 Deck (31):

1

##
Here is a vector:

(x)

(y)

What does x and y represent?

###
x = right

y = up

2

##
Here is a vector:

(-a)

(-b)

What does a and b represent?

###
a = left

b = down

3

##
Here is a vector:

(f)

(-g)

What does f and g represent?

###
f = right

g = down

4

## Define congruent

###
Shape: Same size and shape

Angles: Same measure (degrees)

Sides: Same length

5

## Define similar

### Two figures that have the same shape. Ratios of lengths or angles are equal (e.g. enlargement).

6

## What are the three important things to remember about bearings?

###
1) Measured from north.

2) In a clockwise direction.

3) Written as three figures.

7

##
Complete the sentence:

The mean is always...

###
...between the lowest and highest numbers.

8

## What does Σ mean?

### Sigma, meaning "sum of".

9

## What does ∅ mean?

### "Empty set"

10

## What does A ∩ B mean?

### A intersect B (both A and B)

11

## What does A ∪ B mean?

### A union B (A, B or both)

12

## What does A' mean?

### Not A

13

## What does A ∪ B ∩(A ∩ B)' mean?

### A union B but not A intersect B

14

## What does ∩ mean?

### But/And

15

## Define positive correlation

### As one quantity increases so does the other.

16

## Define negative correlation.

### As one quantity increases, the other decreases.

17

## Define no correlation.

### Both quantities vary with no clear relationship.

18

## What should you do when asked to estimate values of one variable in comparison to the other on a graph?

### Draw the line of best fit.

19

## On scatter graphs, how can we describe the relationship between the data?

###
We can describe the relationship as:

A positive correlation

A negative correlation

No correlation

20

## The line of best fit...

###
Shows the general trend of two points.

Must be straight

Does not have to go through the origin or any of the points

21

## Frequency polygons are...

###
Plotted at the midpoint

Drawn with straight lines

22

## What do you need to help you find out the average in a set of grouped data?

###
Data

Frequency (f) and total

Midpoint (mp)

Midpoint * Frequency (mp*f) and total

23

## How do you find the maximum range with a set of grouped data?

###
Highest Nº in data - Lowest Nº in data = range

(Data table)

24

## How do you find the modal group with grouped data?

### Look at which group has the highest frequency (frequency table).

25

## How do you find the mean estimate in a set of grouped data?

###
mp*f total / f total = mean estimate

(mp*f table, frequency table)

26

## How do you find the median in a set of grouped data?

###
f total / 2 = x

Add frequencies up until you reach x

(frequency table)

27

## On a map with a scale of 1:3,000,000 the distance between Edinburgh and London is 18cm. What is the actual distance, in kilometres, between these cities?

###
18cm*3,000,000cm = 54,000,000cm

100cm = 1m

54,000,000/100 = 540,000m

1000m = 1km

540,000/1000 = 540km

28

## The actual distance between two places in 2.4km. If a map has a scale of 1:40,000 what distance on the map is used to represent it?

###
2.4km = 2400m

2400m = 240,000cm

240,000/40,000 = 6cm

29

## Point B is 100m away from point A. The map uses a scale of 1:1000. What distance is shown on the map to represent this?

###
100cm = 1m

100cm*100 = 10,000cm

10,000cm/1000 = 10cm

30

## Rewrite the interval 11-20 using inequalities.

### 10.5 < x ≤ 20.5

31